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Saturday, August 7, 2021

Medicinal Teas of Hawaii: Mamaki and Ko’oko’olau



Mamaki (Pipturus albidus)  is a Hawaiian endemic plant occurring on all the main Hawaiian Islands except Ni'ihau and Kaho'olawe. It grows in moist to wet forests at elevations ranging from close to sea level to 6,000 feet. Mamaki ranges in height from 6 to 20 feet tall.

Dried or fresh mamaki leaves are used to make a tea often drunk by those feeling lethargic. The tea is also used to help with many internal disorders for the stomach, colon, bladder, liver, and bowels.  The fruit is eaten as a laxative or for stomach, colon and digestive problems. Infused leaves can be used in treatment for high blood pressure, high cholesterol, liver problems, and bladder problems.  In some people mamaki can cause mild agitation or insomnia.





Mamaki is the primary food source for caterpillars of the native Kamehameha butterfly. Planting this shrub in the garden will provide food for the butterfly as well as a healthy, invigorating tea for the gardener.

Mamaki is a highly variable plant. The leaves are dark-green on the top and white to gray underneath. Some varieties have reddish veins.  It is generally not suited for hot, dry coastal settings, but will grow well in urban landscapes with some shading. It will also do well planted in containers in part shade. The red-veined varieties appear to tolerate full sun better than green-leaved varieties. The mature plant recovers after pruning if no more than one-third is removed.

Mamake plants are usually propagated from seed. The fruit can be ripened in a plastic bag to soften the pulp. Seeds are then removed from the pulp by rubbing the fruit in a strainer under running water. The viable seeds will sink and the fruit pulp and other debris can be poured off. Seeds then need to be dried on a paper towel and stored. Once planted, seedlings will thrive in a well-drained soil in a semi-shaded to shaded location.  The plants can also be propagated from cuttings.   


Ko’oko’olau Bidens menziesii is in the sunflower or aster family.  It can be an annual or perennial shrub, ranging from 3 to 12 feet in height, growing in a wide range of habitats. The plant is found on Molokai and West Maui and on the leeward slopes of Mauna Loa and Mauna Kea on the Big Island.  It is easy to grow, preferring full sun and light to moderate watering. It grows well as a potted patio plant.

Ko’oko’olau was widely used by Hawaiians prior to European arrival. Its leaves were used as a revitalizing tea. Flowers were used to stimulate appetite. Today the tea is still sold; however, Bidens pilosa is often the species incorrectly labeled and sold as the traditional Hawaiian tea. 

Tuesday, July 13, 2021

Squash Plants Produce Lots of Bloom But Little Fruit


 
 Squash, along with melons and cucumbers belong to the same plant family called cucurbits (cucurbitaceae). These vegetable plants bear two kinds of flowers on the same plant, male and female.  In order to produce fruit, the pollen from the male flower must be transferred to the female flower. Since the pollen of cucurbits is sticky, wind-blown pollination will not occur. Instead, insects do the major pollination work –honeybees being the main workers.  So, if bees aren’t frequenting your garden, for whatever reason, the fruit set on your squash, cucumbers and melons will be poor. 

Hand pollination, although a tedious chore, can be accomplished by transferring the pollen from the male flower to the female flower, often done with a small artist’s paintbrush.  Female flowers can easily be distinguished from the males by the presence of a miniature fruit at the base of the flower. 

Sometimes gardeners are concerned because none of the first blooms produce  fruit.  This is because the first flowers produced on the plants will be male. In time, female flowers are produced.  Also remember that cucumbers, melons and squash do not cross-pollinate; a cucumber will not cross with a melon; a squash will not cross with a cucumber, etc.  But within each species, cross pollination often occurs. A zucchini squash can pollinate a crookneck squash, and a Crenshaw melon can pollinate a Casaba melon.  Planting the seeds from these crosses will produce fruit that will be different from either parent.

Thursday, June 3, 2021

Gold Dust Day Gecko



The Gold Dust Day Gecko, a native to Madagascar, sometimes referred to as the Madagascar Day Gecko, does well in a tropical climate. Unlike most geckos, it is a diurnal animal, active during the day. They are territorial animals; males are especially aggressive towards other males.

These geckos are very colorful, usually bright green or a yellowish green. Halfway down their backs, they have three red teardrop markings. A blue shade is present around the eyes with bright gold markings on the back and neck. They feed on various insects and other invertebrates and are capable of eating other smaller lizards. They also eat soft, sweet fruit as well as pollen and nectar from flowers.  But they don’t bite humans.

Although these geckos will come into the house, probably looking for food, they are an arboreal species, spending most of their time in trees. If exclusion is desired, treat them as you would mice, rats and cockroaches; make sure to screen all windows, doors, ventilation passages and any small openings into the house.

Another species of gecko is the House Gecko, residing with humans in homes rather than in the wilderness. Being aggressive, this pale brown gecko drives other species away from the house. They are primarily nocturnal.

There are over 900 species of geckos worldwide, but only seven or eight reside in Hawai`i. Geckos are the only lizards who are able to make sounds, other than hissing.  Feeding on cockroaches, mosquitoes, ants, termites and moths, geckos are beneficial to home owners.

It has been thought that geckos are able to run up and down walls and ceilings due to tiny suction cups on their toe pads. However, recently scientists found that geckos have a network of tiny hairs and pads on their feet. With millions of hairs on each foot, the combined attraction of the weak electrical forces allow the gecko to stick to virtually any surface, even polished glass.

Saturday, April 24, 2021

Black Sooty Mold





What is the black, sticky substance that may be found covering the leaves of many plants?
The black substance on the leaves is called sooty mold.  It is a fungus which resembles soot. This particular fungus, however, is not harmful to the plant but is actually living on a sweet, sugary substance called honeydew.  The honeydew is being secreted by some insect that is infesting the plant. If you see sooty mold on a plant, it means that the plant has an insect infestation – most likely aphids, mealy bugs, soft scale or whitefly. 


As the insect feeds, a clear sugary liquid is secreted by the insect onto the leaf below.  It is on this secretion that the mold grows.  Heavy rains will wash off the sooty mold from the leaves, but the insect problem still needs attention. Often when large trees become heavily infested with certain insects, the honeydew can actually be seen raining down upon the ground.  Again, sooty mold indicates an insect problem; inspect the plant for bugs.  Below is a close up of the sooty mold.

Sunday, March 21, 2021

Moss and Algae = Slippery Sidewalks


Living in the tropics, people are often plagued with unsightly and dangerous moss and algae growing on driveways and pathways around their homes.  When the rain stops, the green growth will dry but will regenerate again with the next rain. 

There are many different products on the market to help clean up the driveway.  Look at the active ingredients on the label; most products will contain bleach,  soap, or a form of copper. Be sure to follow the directions on the label.  Most products are applied and remain for a while and then washed off with a hose or scrapped with the help of a shovel.  At times the buildup is so great that a power washer is needed. Bleach is often recommended at one cup per gallon of water. 

When using copper and bleach, there is always the potential for these products damaging desired plants either from the direct spray or from the solution saturating the soil. Take caution when spraying near desirable plants. The damage is lessened in high rainfall areas through the leeching action of the rain.

Another option is to use one cup of vinegar per gallon of water; bleach is sometimes added to fortify the solution. An application of Roundup herbicide will kill the algae and moss, but the plant residue needs to be scrapped away. 





Tuesday, February 9, 2021

Composting



Composting is a good way to reuse our natural resources, recycle nutrients and add good organic matter back into the soil.  

The popular practice of composting is defined as the process by which organic materials biologically decompose under controlled conditions. Perhaps the most notable point about composting is not to make it more complicated than it is.  By merely throwing a pile of twigs and leaves in the back corner of the garden, you are composting; of course, it may take a year or so to breakdown.  But by following a few simple rules you can speed up the process and produce good compost in about a month or so. The following are key principles:

 a. Proper moisture and air (oxygen) content - Compost works best if the moisture content of the materials is about 50%.  That’s not easy to measure, but it has been estimated to be approximately the moisture content of a wrung-out sponge.  If the material is too dry, decomposition will stop; if too wet, oxygen is excluded, and decomposition will slow and may smell bad. 

b. Proper carbon/nitrogen ratio - For effective composting, the raw materials must have a proper carbon/nitrogen ratio – set at about 30:1.  Since this too cannot be easily measured, mixing equal volumes of green plant material with equal amounts of brown plant material will give this ratio. The greens are fresh moist materials like grass clippings, weeds, manures and kitchen scraps. The browns are dry materials such as twigs, wood chips, straw, saw dust and paper.  If a pile of twigs are thrown to the side, they will eventually decompose. When leaves (greens) are combined with the twigs (browns) in the proper ratios, decomposition will occur more rapidly.    
Mixing grass clippings with twigs or chips is not only good for obtaining the proper ratio but also helps to maintain a good oxygen level.  Grass clippings or shredded papers alone tend to mat and exclude oxygen.  Adding twigs helps to open the pile allowing a better movement of air.   

c. Proper size of material - Soft, succulent plant tissue doesn’t need to be chopped into small pieces because it will decompose rapidly. Woody materials, however, will decompose better if pieces are ½ to 1 ½ inches in size: the smaller the pieces the quicker the decomposition.

d. Proper pile size - The size of the compost pile is important.  The minimal size is 3 cubic feet (3x3x3). Maximum size would be around 5x5 and as long as desired.

e. Proper turning- Turning the pile is not required but will certainly speed up the process if turned every day to every ten days. Turning helps ensure proper air circulation, moisture and heat distribution. 

What should NOT be put into the compost pile? Meat, fat, manure from meat-eating animals as well as human waste. Manure from herbivores such as goats, cows, horses, rabbits and even elephants can be used.  Don't throw diseased plants into the compost pile, because the pile may not reach the temperatures that are required to kill plant diseases and weed seeds. 
Finally, here’s how to know when the composting is ready: the majority of the pile has become dark, loose, crumbly and sweet smelling.  Also, the original materials will not be recognizable with the exception of a few pieces of tough woody material. 

Saturday, January 9, 2021

Seed Germination - Nothing's coming up!





Planting a vegetable garden has a variety of challenges. But how disappointing when the seeds are planted and nothing comes up! Here are primary reasons for poor seed germination.

 1. Planting depth – small seeded vegetables like carrots and onions can easily be planted too deep. If planted too close to the surface, the seed can easily be washed away during heavy rains. Consult the seed packet for proper planting depths. 

2. Temperature – some seed need the soil temperature to warm up before they will adequately germinate, while other cool season vegetables like onions, germinate best in a cool soil. 

 3. Water -  too little and seeds will not germinate or will dry up after germination. With too much water, seeds and seedlings can die from lack of oxygen or be overcome by fungi. Even under normal moisture conditions, different species of fungi and bacteria can cause seeds to rot.  Seeds and seedlings should always be kept moist, but the soil should not remain soaking wet.  

 4. Soil pH - each vegetable seed as well as other plants will have its range in which it will germinate best. 

5. Herbicide residues -  may still be active in the soils causing poor germination.  A high fertilizer content in the soil could also hamper germination. 

6.  Insects will often feed on  seeds and young seedlings.

7. And finally, the seed itself! Poor seed germination can particularly be a problem in humid climates.  Relative humidity influences the moisture content of the seed. The higher the moisture content, the lower the germination rate will be, especially, after one year.


As a general rule, vegetable and flower seeds can be kept for one year without appreciable decrease in germination. Storage, however, may be extended to 10 or more years under proper conditions; seed moisture and temperature are the most important factors. The drier the seeds, the longer they will store.

In humid climates such as Hawaii, storing vegetable seeds in a dry, sealed glass container should keep most seeds viable for a year. For longer storage, place seeds in a moisture-proof container and store in the refrigerator.

Longevity of vegetable seeds will also vary depending on the species.  For example, collards, cucumber, endive, radish and water cress produce some of the hard seeds, rated as lasting 5 years. Next come beets, cabbage, cauliflower, eggplant, kale, mustard, squash, swiss chard, tomato, turnip, watermelon, rated at a 4 year longevity; asparagus, beans,  carrot,  celery,  chinese cabbage, New Zealand spinach, pea, and spinach, at 3 years; leek,  sweet corn, okra and pepper are rated at 2 years; and finally, the last group is rated at a mere 1 year longevity - lettuce, parsley, parsnip and onion.



Photo: Purdue University